crustal shortening

Crustal shortening in geology refers to the process where the Earth's crust is compressed horizontally, leading to a reduction in its length and an increase in its thickness. This phenomenon is a primary mechanism in the formation of major mountain belts, such as the Alps and the Himalayas.1

When two continental plates collide, the crust is pushed together, causing it to buckle, fold, and thrust upwards. This results in the formation of extensive fold and thrust belts, where layers of rock are deformed and stacked on top of each other. The immense pressure involved can cause significant uplift, creating high mountain ranges composed of crystalline rocks that were once deep within the Earth's crust. This process is a key aspect of diastrophism, the large-scale deformation of Earth's crust.12